In textile machines which process yarn, it is often necessary to provide a mechanism for taking-up of a predetermined length of yarn and for supplying of this yarn to the textile machine for various purposes. This is particularly true in the case of two-for-one twister textile yarn processing machines utilizing pneumatic or other types of automatic threading mechanisms for threading-up the spindle assemblies thereof upon starting-up of the spindle assembly or following breakage of the yarn during yarn processing. Such two-for-one twister textile yarn processing machines with pneumatic threading mechanisms for threading-up the spindle assembly are disclosed in U.S. Pat. No. 3,731,478, issued May 8, 1973, and U.S. Pat. No. 3,975,873, issued Aug. 24, 1976, both of which are assigned to the assignee of the present invention.
As may be seen in both of these U.S. patents, there is provided a two-for-one twister or the like textile yarn processing machine having a plurality of spindle assemblies each including a driven rotating rotor mechanism, a stationary carrier mechanism for carrying a hollow supply package of yarn, and an elongate yarn passageway extending downwardly through the top of the carrier mechanism along the axis of the spindle assembly and radially outwardly through the rotor mechanism for receiving the yarn from the supply package therethrough and then upwardly along the outside of the carrier mechanism for forming a rotating balloon of yarn during yarn processing and which is subsequently taken-up by a take-up mechanism. There is also described in these U.S. patents selectively-operable pneumatic threading mechanisms for automatically threading yarn withdrawn from the supply package through the passageway of the spindle assembly by creating a suction through the yarn entry portion of the passageway and a positive air stream through the yarn exit portion of the passageway.
In order to accomplish suitable pneumatic threading-up, the yarn must be pulled from the supply package of yarn and supplied to the entry of the yarn passageway through the spindle assembly in a substantially tension-free condition so that the suction and positive air stream created through the yarn passageway in the spindle assembly can effectively thread the yarn therethrough. Often, problems have existed with respect to removing the yarn from the supply package and supplying it to the passageway in the spindle assembly for automatic pneumatic threading in a substantially tension-free condition. Accordingly, there is a need in these types of machines for a yarn take-up and supply mechanism which can take-up and store a given length of yarn and supply the stored yarn to the textile machine in a substantially tension-free condition.
Heretofore, yarn take-up and supply mechanisms, also called yarn regulating devices, have been typically used in weaving and knitting machines and were instrumental in insuring the slip-free positive supply of fixed lengths of yarn at high yarn running speeds to these machines. Such yarn storage devices are disclosed in U.S. Pat. No. 4,028,911, issued June 14, 1977; U.S. Pat. No. 3,687,384, issued Aug. 29, 1972; U.S. Pat. No. 3,672,590, issued June 27, 1972 and U.S. Pat. No. 3,648,939, issued Mar. 14, 1972.
In the yarn take-up and storage devices of these U.S. patents, the yarn runs onto one end of a take-up drum from a supply package and is passed directly onto the yarn processing machine, such as a circular knitting machine, from the other end of the drum. An axial displacement of the yarn windings on the drum takes place along the surface of the drum by a pinwheel gear member having teeth thereon which project into the circumference of the drum and move the windings of yarn forwardly on the drum as they are taken off from one end of the drum and are formed on the other end of the drum. These types of yarn take-up and storage mechanisms are continuously utilized during the supply of yarn from the supply packages to the yarn processing machines and remain in the feeding path or zone of yarn flow during the entire machine operation.
Accordingly, these previously known yarn take-up and storage devices cannot be utilized for intermittently taking-up and storing a given length of yarn and then supplying this store of yarn in a substantially tension-free condition to an associated textile machine, such as for use during a threading-up operation of the machine, and which would thereafter not be in the normal path of travel of the yarn through the textile machine during processing of the yarn therein.